Other papulosquamous dz Flashcards
What cells are involved in small plaque parapsoriasis?
CD4+ T cells
What is the estimated progression from large plaque parapsorasis to MF
10-35%
What are the differences in T-cells in PLEVA vs PLC?
CD8+ in PLEVA and CD4+ in PLC
Clinical presentation of PLEVA?
Rapid onset of widespread (trunk, buttocks, proximal extremities) pink papules, evolve into vesicular ulceronecrtoic purpuric and cursted papuels.
Heals with varioliform scars after weeks
Clinical of PLC?
widespread scaly red-brown papules and plaques. Resolves w/ hypopigmentation after weeks to months
What clinical feature can predict the length to resolution for PLC?
More widespread = shorter time to resolution. Less widespread = longer
Pneumonic for PLEVA path?
Parakeratosis Lichenoid infiltrate Extrravased RBC V-shaped dermal lymphocytic infilate Acute epidermal changes (dyskeratosis, ulceration, neutrophilic scale crust) CD8
What cell should you not see in PLEVA or PLC on path?
Eos!
Age distribution of PRP?
Bimodal: 1st and 6th decade
First sign of PRP?
Folliculocentric keratotic papules on erythematous base (nutmeg-grater)
Other clinical features of PRP?
Scalp erythema, diffuse scaling, folliculocentric keratotic papules on erythematous base, orange-red waxy keratoderma of palms soles, rash spreads caudally
What type of PRP is most common in kids?
Type IV or circumscribed juvenile
What form of PRP is inherited/familial?
V/atypical juvenile
Clinical findings in PRP a/w HIV?
follicular spines, acne conglobata, hidradenitis suppurativa
Epi of Pityriasis rosea?
adolescents and young adults
Christmas tree ddx?
PR, KS, secondary syphillis, SK, parapsoriasis/mycosis fungoides, lichen planus pigmentosus/ashy dermatosis
What causes PR?
HHV-7 and HHV-6 commonily
Drugs a/w PR?
ACEI, gold, B-blocker are the big ones. Also NSAIDS, bismuth, barbiturates, isotretinon, metronidazole, clonidine
Natural course of PR?
goes away spontaneously over 6-8 weeks
What is the VIDAL type of PR?
Recurrent or persistent PR
What medication can shorten the dz course in PR?
Erythromycin
PR issues in pregnancies?
There is an association as a report of a possible risk of sponateous abortion
Etiology of granular parakeratosis?
defect in filaggrin meatbolism –> retention of keratohyaline granules in stratum corneum.
What defines small plaque vs large plaque parasporasis?
small plaque = <5cm in diameter large plaque = >5cm in diameter
Clinical presentation of parapsoriasis?
Chronic, usually asymptomatic patches or thin plaques with fine-scale Color varies from pink to red-brown +/- epidermal atrophy/poikiloderma (large plaque parapsoriasis).
Age distribution for small plaque parapsoriasis?
Peaks during 5th decade
Sex differences in small plaque parapsoriasis?
M:F 3:1
What are the plaques made up of in small plaque parapsoriasis?
Superficial cutaneous lymphoid infiltrates composed primarily of CD4+ T-cells.
What is the histology of small-plaque parapsoriasis?
Mild non-specific spongiotic dermatitis with focal parakeratosis, +/- exocytosis of lymphocytes
The difference in pathophysiology between small and large plaque parapsoriasis?
Dominant T-cell clonality is seen in pt’s with large plaque parapsoriasis. In some cases, it may actually be patch stage mycosis fungoides.
What form of large-plaque parapsoriasis virtually always progresses to mycosis fungoides?
Retiform varients (rare)
Progression of large plaque parapsoriasis to more overt forms of lymphoma?
10-35% over 6-10 years.
Tx for small plaque parapsoriasis?
Topical CS, calcineurin inhibitors, coal, light therapy, topical bexarotene, imiquimod. If there is itching then you can use antihistamines.
Difference clinically between PLEVA and PLC lesions?
PLEVA lesions are crusted and occasionally vesiculpustular whereas in PLC they are scaly
Pt hx of PLEVA/PLC?
Recurrent crops of spontaneously regressing erythematous papules. This is important as PR will have the herald patch and then all the lesions will go away, you wont get recurrent lesions nearly as commonly.
What is the difference in T-cell infiltrates in PLEVA vs PLC?
PLEVA = CD8+ t-cell predominance, PLC = CD4+ predominance
What can trigger PLEVA/PLC?
Infx: HIV, parovirus B19 Drugs: estrogen-progesterone, TNF-a inhibitors (infliximab and adalimumab), statins, radiocontrast dye low-grade T-cell lymphoproliferative dz.
What type of dz is PLEVA often considered?
T-cell lymphoproliferative diosrder (more so than PLC) as there is more t-cell clonality in PLEVA as compared to PLC
Key clinical findings in PLEVA?
Rapid onset of widespread (trunk, buttocks, proximal extremities> other sites) pink papules that evolve into vesicular, ulceronecrotic, purpuric, and crusted papules which then heal with varioliform scars after weeks
What is Mucha-Haberman dz?
This is PLEVA but with high fevers, consitutional sx’s, LAD, arthritis, mucosal involvement, pulmonary involvement, and GI involvement. (increased TNF-a levels)
Clinical findings of PLC?
Widespread, scaly, red-brown, papules and plaques Resolves with hypopigmentation after weeks to months (longer than PLEVA) Adults: PLC > PLEVA More diffuse distribution= shortest disease course (avg 11 months) Limited/peripheral distribution= longest disease course (avg 33 months)
Clinical progression of PRP?
Begins on the head/neck and progresses caudally
Nail findings in PRP?
Thick yellow-brown nails w/ subungal debris; no nail pits like psoriasis.
Tx for PRP?
Isotretinoin (unlike psoriasis), acitretin, high dose vit A, MTX, TNFa inhibitors, phototherapy
What are the genetic findings in Type V PRP (atypical juvenile)
Heterozygous gain of function mutation in CARD1 aka PSOR2 psoriasis susceptibility gene
What is the “Wong type” of PRP eruption?
PRP eruptions seen in pt’s with dermatomyositis
Describe Type I PRP
Classic PRP in adult. spreads caudally, red-orange plaques w/ islands of sparing, perifollicular keratotic papules, waxy palmoplantar keratoderma.
most clears within 3 yrs
represents 55% of PRP
Describe Type II PRP
Adults, areas of eczematous dermatitis, ichythyosiform scale on legs, keratoderma w/ coarse lamellated scale, occasional alopecia
Chronic course
5% of PRP
Describe type III PRP
Classic Juvenile Findings seen in type I, peak onset is first 2 yrs of life and adolescence.
clears in 3 years
10% of PRP
Describe type IV PRP
Focal Juvenile PRP -M/c on the elbows and knees, erythema, follicular papules, prepubertal onset.
variable course
25% of PRP
Describe type V PRP
Atypical Juvenile Follicular hyperkeratosis, erythema, scleroderma-like changes of hands and feet, accounts for most familial cases of PRP w/ mutations in CARD1 (PSOR2), onset in the first few years of life
chronic course
5% of PRP
Describe type VI PRP
HIV associated PRP -overalp w/ type I -other findings = follicular spines, acne conglobata, HS
most rare form= <1%
What is granular parakeratosis
Primary lesions are brownish-red keratotis papules that can coalesce into plaques. Adult form is almost exclusvely in women. Most cases are in the axillae but can be in other intertrigineous sites too.
infantile form is a/w diaper wearing and can be b/l plaques in inguinal folds or erythematous geometric plaques under pressure points from diaper.
Histopathology of granular parakeratosis?
This is really the key to the name, there is distinct retention of the keratohyalin granules in the parakeratosis.
Tx for granular parakeratosis?
topical: corticosteroids, vitamin D analogs, keratolytics, and antifungals,
destructive: cryotherapy, systemic: isotretinoin, antifungals
